Nanometer-order micropatterning techniques continue to improve, with the semiconductor industry taking the initiative, and patterning at a level of a few tens of nanometers to a few nanometers has recently become possible. Patterning techniques are used not only in the semiconductor field but also in various other fields such as displays, electronic materials, catalysts, and memory materials.
In particular, it is being contemplated to apply micropatterning techniques to hard disk drives (HDDs). It is possible to increase the magnetic particle volume per bit and increase the thermal stability by patterning the recording medium of an HDD. Also, jitter noise can be reduced because particle sizes can be made uniform compared to a granular medium manufactured by sputtering. A magnetic recording medium like this is called a patterned medium (patterned media). In this patterned medium, it is important to make the sizes and arrangements of patterned magnetic particles uniform.
In a device having a nanostructure such as a patterned medium, fine particles can be applied as a template for forming the nanostructure. It is possible to transfer a fine particle shape to a magnetic recording medium or anti-reflection film, and grow a carbon nanotube (CNT) by using fine particles themselves as a catalyst. It is necessary to uniformly arrange particles on a substrate and subject the particles to a subsequent process regardless of whether the particles form a monolayer or multiple layers. During the process, the surface of each fine particle is exposed by etching a protective group covering the surface of the fine particle. This process poses the problem that the particles are charged by plasma and aggregate to each other.